It goes without saying, at least in today's day and age, that smoking while pregnant is a bad idea and very bad for the fetus. But new research demonstrates what the ill effects can really be. Danish researchers reported in Circulation: Journal of the American Heart Association that pregnant women who smoke have lowered production of a chemical substance that relaxes blood vessels. That, in turn, reduces the blood flow to the uterus and results in stunted growth including lower birth weights, shorter birth lengths and smaller heads.
Smoking harms the fetus
"This study is one of the first to show a biochemical measurement of what is going on to cause the lower birth weight," said Malene Rohr Andersen, M.Sc., Ph.D., lead author of the study and project manager of the Department of Clinical Biochemistry at Gentofte University Hospital in Denmark. "We have known for 50 years that infants born to mothers who smoke during pregnancy have lower birth weights. But this study provides a possible explanation of why there is restricted blood flow to the fetus. Reduced production of the vasodilator nitric oxide may lower the blood flow to the fetus."
The fetus needs good blood flow to develop properly. However the researchers found that the enzyme that produces nitric oxide, a chemical needed to regulate blood flow, was 47 percent less in smoker' umbilical cords.The activity in blood vessels was 36 percent less as a result.
Babies born to the smokers weighed 25 percent less than their nonsmoker counterparts on average, according to the research.
It's not too late to quit
The good news for smokers who are expecting is that if you quit early in pregnancy, then enzyme levels can return to normal, allowing the baby to be born at a normal birth weight.
"Women who smoke should stop smoking if they plan to become pregnant, or at the very least should stop smoking as soon as they find out they are pregnant," Andersen said. "Women should also not start smoking again once they have delivered. Some women stop smoking during pregnancy, only to start up again after the baby is delivered and the child is then exposed to environmental smoke, which also affects vascular function."
Tips to quit smoking during pregnancy
Quitting smoking isn't easy for anyone, but these tips will help you from lighting up
1. Cold Turkey: If you are pregnant, the best bet might be to quit cold turkey, but it can be really tough, and resisting the urge to smoke will be challenging. But when you have a baby to worry about, the stakes are raised.
2. Gradually stopping: "In pregnancy you can quit cold turkey, or you can slowly decrease the number of cigarettes you have each day over a few weeks," says DrSpock.com.
3. Chewing gum: Some quitters find that replacing cigarettes with gum can be an effective technique for stopping smoking because it keeps your mouth busy.
4. Avoid contact with smokers: Enlist nonsmoking friends and family members to encourage you, and try to limit contact with smokers while they are smoking. And never, ever let anyone make you feel bad for the decision. Not smoking is best for baby, and for you.
5. What about Nicotine Replacement Therapy? Some experts believe the risks of smoking outweighs the risks associated with nicotine replacement therapy, however other experts disagree. Lela Bryan, chief learning officer for Nicotine Solutions, says the patch should never be used during pregnancy. "Nicotine patches, gum, nasal spray, or lozenges are harmful to pregnant women because it is not only the smoke that is harmful but the nicotine is a poison," Bryan said, adding that the nicotine could potentially be absorbed by the fetus, causing harm. Dr. John Martin of Banner Good Samaritan Medical Center and medical director of the hospital's women's center recommends using nicotine replacement therapy before you get pregnant.
Our advice? Stick it out and quit smoking naturally, without the use of nicotine replacement therapy and its potentially harmful side effects.
6. Support system: No matter what technique you use, it's important to have support in your quest for a smoke-free pregnancy. Enlist the help of your husband, parents, friends, family and doctor to give you the encouragement and will power you need to make it through this period.
Resources for quitting
The March of Dimes has a great resource on their website (Marchofdimes.com)with tips and advice on quitting smoking.
Also check out these articles for more information on quitting smoking: